The Internet Protocol (IP) multimedia subsystem (IMS), defined by the 3rd Generation Partnership Project (3GPP), is an architectural framework for implementing IP-based telephony and multimedia services. IMS defines a set of specifications that enables the convergence of voice, video, data and mobile technology over an all IP-based network infrastructure. In particular, IMS fills the gap between two of the most successful communication paradigms, cellular and Internet technology, by providing Internet services everywhere using cellular technology in a more efficient way. Session Initiation Protocol (SIP) is the main protocol for IMS. IMS aims to ensure that IMS applications work consistently across different network infrastructures.
Current IMS SIP call flow systems provide serial and lengthy steps to setup or tear down a SIP session between caller A and called party B. These IMS SIP sessions can originate from an IMS-capable device and terminate at another IMS-capable device, a public switched telephone network (PSTN) or a non-IMS wireless device. SIP setup and/or tear-down processes typically flow serially, with IMS network elements sending each other similar and redundant SIP message commands. Examples of SIP message commands include INVITE, REFER, BYE and the like. In general, a SIP INVITE message is forwarded from an initiating end user device through to a recipient end user device. These similar and redundant SIP message commands increase the network traffic with a number of SIP message steps that are need to setup and teardown a SIP session. As a result, more network resources are occupied with the exchange of the similar and redundant SIP message commands.
In recent years, as the number of mobile devices using network resources increases, the need for additional network bandwidth has also increased. Different techniques have been suggested for optimizing the use of the available network resources and bandwidth including techniques for more efficiently managing processes that use the available bandwidth.
However, a need still exists for a system and method for effectively managing use of network resources to reduce the exchange of similar or redundant SIP commands.